Hydraulic cylinder impact-buffering assembly

Abstract

A hydraulic cylinder impact-buffering assembly has an outer cylinder and a piston rod. The outer cylinder is a hollow tube and has an opening. The piston rod is movably connected to the outer cylinder and has a piston. The piston is securely connected to the piston rod, is movably mounted in the outer cylinder and has a connecting segment and a flowing segment. The connecting segment is securely connected to the piston rod and has a connecting recess, a ball recess, multiple side leaking holes, a leaking ball and a spring. The flowing segment is formed on and protrudes from the connecting segment and has a mounting recess, an oil ring, a central recess, multiple first guiding holes and multiple second guiding holes.

What is claimed is: 
     
         1 . A hydraulic cylinder impact-buffering assembly comprising:
 an outer cylinder, the outer cylinder being a hollow tube and having a distal end, a proximal end and an opening formed through the proximal end of the outer cylinder; and
 a piston rod, the piston rod movably connected to the outer cylinder and having an inner end movably mounted in the outer cylinder via the opening, an outer end, an external surface and a piston, the piston securely connected to the piston rod, movably mounted in the outer cylinder and having a connecting segment and a flowing segment, the connecting segment securely connected to the inner end of the piston rod and having a connecting end, a forming end, an external surface, an outer diameter, a connecting recess, a ball recess, multiple side leaking holes, a leaking ball and a spring, the connecting recess axially formed in the connecting end of the connecting segment, mounted around and connected to the inner end of the piston rod, the ball recess axially formed in the forming end of the connecting segment and communicating with the connecting recess, the side leaking holes radially formed in the external surface of the connecting segment at intervals and communicating with the ball recess, the leaking ball mounted in the ball recess between the side leaking holes, the spring mounted in the ball recess and abutting the inner end of the piston rod and the leaking ball to enable the leaking ball to locate between the side leaking holes, the flowing segment formed on and protruding from the forming end of the connecting segment and having an outer diameter larger than the outer diameter of the connecting segment, a forming end formed with the forming end of the connecting segment, a flowing end, a middle, an external surface, a mounting recess, an oil ring, a central recess, multiple first guiding holes and multiple second guiding holes, the mounting recess annularly formed in the external surface of the flowing segment at the middle of the flowing segment to form a first flange and a second flange beside the mounting recess, the first flange formed on and protruding from the external surface of the flowing segment between the mounting recess and the side leaking holes of the connecting segment, the second flange formed on and protruding from the external surface of the flowing segment between the mounting recess and the flowing end of the flowing segment, the oil ring mounted around the external surface of the flowing segment in the mounting recess, abutting the internal surface of the outer cylinder and selectively abutting the first flange and the second flange, the central recess axially formed through the forming end and the flowing end of the flowing segment, aligning with an axis of the flowing segment and selectively communicating with the side leaking holes when the leaking ball is moved relative to the connecting segment, the first guiding holes radially formed through the first flange at intervals, communicating with the mounting recess, and each one of the first guiding holes having an inner diameter, and the second guiding holes radially formed through the second flange at intervals, communicating with the mounting recess, and each one of the second guiding holes having an inner diameter different from the inner diameter of each one of the first guiding holes. 
   
     
     
         2 . The hydraulic cylinder impact-buffering assembly as claimed in  claim 1 , wherein the inner diameter of each one of the second guiding holes is larger than the inner diameter of each one of the first guiding holes. 
     
     
         3 . The hydraulic cylinder impact-buffering assembly as claimed in  claim 2 , wherein
 the outer cylinder has a sealing block mounted in the outer cylinder and adjacent to the opening to seal the opening; and   the inner end of the piston rod is movably mounted in the outer cylinder via the opening and the sealing block.   
     
     
         4 . The hydraulic cylinder impact-buffering assembly as claimed in  claim 3 , wherein the outer cylinder has a connecting head connected to the distal end of the outer cylinder. 
     
     
         5 . The hydraulic cylinder impact-buffering assembly as claimed in  claim 4 , wherein
 the piston rod has an outer thread formed on the external surface of the piston rod at the inner end of the piston rod; and   the connecting recess of the connecting segment has an internal surface and an inner thread formed on the internal surface of the connecting recess and screwed with the outer thread of the piston rod.   
     
     
         6 . The hydraulic cylinder impact-buffering assembly as claimed in  claim 5 , wherein
 the leaking ball is mounted in the ball recess to abut against the forming end of the flowing segment to close a passage between the central recess of the flowing segment and the side leaking holes of the connecting segment; and   the spring is mounted between the leaking ball and the inner end of the piston rod.   
     
     
         7 . The hydraulic cylinder impact-buffering assembly as claimed in  claim 1 , wherein
 the outer cylinder has a sealing block mounted in the outer cylinder and adjacent to the opening to seal the opening; and   the inner end of the piston rod is movably mounted in the outer cylinder via the opening and the sealing block.   
     
     
         8 . The hydraulic cylinder impact-buffering assembly as claimed in  claim 1 , wherein the outer cylinder has a connecting head connected to the distal end of the outer cylinder. 
     
     
         9 . The hydraulic cylinder impact-buffering assembly as claimed in  claim 2 , wherein the outer cylinder has a connecting head connected to the distal end of the outer cylinder. 
     
     
         10 . The hydraulic cylinder impact-buffering assembly as claimed in  claim 1 , wherein
 the piston rod has an outer thread formed on the external surface of the piston rod at the inner end of the piston rod; and   the connecting recess of the connecting segment has an internal surface and an inner thread formed on the internal surface of the connecting recess and screwed with the outer thread of the piston rod.   
     
     
         11 . The hydraulic cylinder impact-buffering assembly as claimed in  claim 2 , wherein
 the piston rod has an outer thread formed on the external surface of the piston rod at the inner end of the piston rod; and   the connecting recess of the connecting segment has an internal surface and an inner thread formed on the internal surface of the connecting recess and screwed with the outer thread of the piston rod.   
     
     
         12 . The hydraulic cylinder impact-buffering assembly as claimed in  claim 3 , wherein
 the piston rod has an outer thread formed on the external surface of the piston rod at the inner end of the piston rod; and   the connecting recess of the connecting segment has an internal surface and an inner thread formed on the internal surface of the connecting recess and screwed with the outer thread of the piston rod.   
     
     
         13 . The hydraulic cylinder impact-buffering assembly as claimed in  claim 1 , wherein
 the leaking ball is mounted in the ball recess to abut against the forming end of the flowing segment to close a passage between the central recess of the flowing segment and the side leaking holes of the connecting segment; and   the spring is mounted between the leaking ball and the inner end of the piston rod.   
     
     
         14 . The hydraulic cylinder impact-buffering assembly as claimed in  claim 2 , wherein
 the leaking ball is mounted in the ball recess to abut against the forming end of the flowing segment to close a passage between the central recess of the flowing segment and the side leaking holes of the connecting segment; and   the spring is mounted between the leaking ball and the inner end of the piston rod.   
     
     
         15 . The hydraulic cylinder impact-buffering assembly as claimed in  claim 3 , wherein
 the leaking ball is mounted in the ball recess to abut against the forming end of the flowing segment to close a passage between the central recess of the flowing segment and the side leaking holes of the connecting segment; and   the spring is mounted between the leaking ball and the inner end of the piston rod.   
     
     
         16 . The hydraulic cylinder impact-buffering assembly as claimed in  claim 4 , wherein
 the leaking ball is mounted in the ball recess to abut against the forming end of the flowing segment to close a passage between the central recess of the flowing segment and the side leaking holes of the connecting segment; and   the spring is mounted between the leaking ball and the inner end of the piston rod.